Subject: CVE-2024-40922: io_uring/rsrc: don't lock while !TASK_RUNNING

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

io_uring/rsrc: don't lock while !TASK_RUNNING

There is a report of io_rsrc_ref_quiesce() locking a mutex while not
TASK_RUNNING, which is due to forgetting restoring the state back after
io_run_task_work_sig() and attempts to break out of the waiting loop.

do not call blocking ops when !TASK_RUNNING; state=1 set at
[<ffffffff815d2494>] prepare_to_wait+0xa4/0x380
kernel/sched/wait.c:237
WARNING: CPU: 2 PID: 397056 at kernel/sched/core.c:10099
__might_sleep+0x114/0x160 kernel/sched/core.c:10099
RIP: 0010:__might_sleep+0x114/0x160 kernel/sched/core.c:10099
Call Trace:
 <TASK>
 __mutex_lock_common kernel/locking/mutex.c:585 [inline]
 __mutex_lock+0xb4/0x940 kernel/locking/mutex.c:752
 io_rsrc_ref_quiesce+0x590/0x940 io_uring/rsrc.c:253
 io_sqe_buffers_unregister+0xa2/0x340 io_uring/rsrc.c:799
 __io_uring_register io_uring/register.c:424 [inline]
 __do_sys_io_uring_register+0x5b9/0x2400 io_uring/register.c:613
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd8/0x270 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6f/0x77

The Linux kernel CVE team has assigned CVE-2024-40922 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 6.4 with commit 4ea15b56f081 and fixed in 6.6.35 with commit 0c9df3df0c88
	Issue introduced in 6.4 with commit 4ea15b56f081 and fixed in 6.9.6 with commit 4429c6c77e17
	Issue introduced in 6.4 with commit 4ea15b56f081 and fixed in 6.10 with commit 54559642b961

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-40922
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	io_uring/rsrc.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/0c9df3df0c888d9ec8d11a68474a4aa04d371cff
	https://git.kernel.org/stable/c/4429c6c77e176a4c5aa7a3bbd1632f9fc0582518
	https://git.kernel.org/stable/c/54559642b96116b45e4b5ca7fd9f7835b8561272